Access Elements of a Nonscalar Structure Array
This example shows how to access and process data from multiple elements of a nonscalar structure
array:
Create a 1-by-3 structure s with field f:
s(1).f = 1;
s(2).f = 'two';
s(3).f = 3 * ones(3);
Although each structure in the array must have the same number of fields and the same field names,
the contents of the fields can be different types and sizes. When you refer to field f for multiple
elements of the structure array, such as
s(1:3).f
or
s.f
MATLAB returns the data from the elements in a comma-separated list, which displays as follows:
ans =
1
ans =
two
ans =
3
3
3
3
3
3
3
3
3
You cannot assign the list to a single variable with the syntax v = s.f because the fields can contain
different types of data. However, you can assign the list items to the same number of variables, such
as
[v1, v2, v3] = s.f;
or assign to elements of a cell array, such as
c = {s.f};
If all of the fields contain the same type of data and can form a hyperrectangle, you can concatenate
the list items. For example, create a structure nums with scalar numeric values in field f, and
concatenate the data from the fields:
nums(1).f = 1;
nums(2).f = 2;
nums(3).f = 3;
allNums = [nums.f]
This code returns
allNums =
1
2
3
Access Elements of a Nonscalar Structure Array
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